Metrizamide-enhanced Computed Tomography as an Adjunct to Metrizamide Myelography in the Evaluation of Lumbar Disc Herniation and Spondylosis

Abstract
Eighty patients with operatively proven lumbar disc herniation or lumbar spondylosis were preoperatively evaluated with metrizamide myelography followed by metrizamide-enhanced computed tomography (CT). The x-ray films were reviewed without knowledge of the operative findings, and the patients were subdivided into those with disc extrusions, spondylosis, or recurrent abnormalities. For the group as a whole, CT was correct in 82% and myelography was correct in 77%. Both CT and myelography together were accurate in 91%, a significant improvement (P<0.02). The authors conclude that, if both studies are performed, the percentage of cases correctly diagnosed is increased. Therefore, both metrizamide myelography and metrizamide-enhanced CT should be obtained in selected cases. A review of the literature is included.